(1) Field of the Invention.
This invention relates to containers for liquids and particularly containers for viscous, difficult to pour liquids and more particularly to bottle-type containers suitable for quick dispensing viscous liquids.
(2) Discussion of the Prior Art.
Glass bottles have been used for the storage and dispensing of both easily flowable and viscous liquids for many years, while plastic squeeze bottles have also been used for a considerable time for dispensing viscous-type liquids. Such bottles may be supplied with the usual screw-type cap, which is removed when liquid is to be dispensed, or may have some other type of closure, including automatic valves which open upon an increase in internal pressure. While these various containers have worked efficiently for viscous liquids when the container is full, as the contents of the container are used it takes longer and longer for such viscous liquid to reach the opening, or valve, in the container, so the liquid can be dispensed. This is because the opening in the container is usually at the top in order to keep the contents away from the closure means, whether in the form of a cap or a valve, in order to decrease the possibility of leakage of liquid during non-use. It is thus necessary to invert the bottle or container and allow the liquid to move or drain to the area of the valve or other closure before the liquid can be dispensed from the container. Such internal drainage can take a significant period even in the case of a plastic squeeze bottle, particularly as the bottle becomes progressively more empty. In our current high paced society the necessity to wait for such drainage to occur before dispensing from a container can take, or seem to take, a significant and frequently frustrating amount of time. For example, in the case of shampoo, the majority of users today apply the shampoo in a shower, which shower is frequently used in the first place because of its quicker or more expeditious cleansing, particularly for those who shower in the morning before leaving for work. To wait for shampoo liquid to drain to the lowest portion of an inverted bottle, therefore, can become quite frustrating and tension inducing for the user. Likewise to wait for ketchup or the like to drain to the lowest portion of a inverted bottle can be frustrating to those accustomed to the instant gratification of their wants and needs, at least with respect to fairly inexpensive items.
It has been suggested in the past that the availability and expeditiousness of dispensing of viscous liquids in particular could be considerably expedited if the liquid were kept more or less continuously adjacent to the dispensing closure. Two principle arrangements for effecting this have been tried or developed. In the first of these, an internal membrane is provided to continuously decrease the size of the containment space within the container as the contents of such container are used. Frequently these internal membranes have taken the form of a soft plastic container or the like provided within an exterior hard container plus a means for providing pressure between the two to keep the internal container membrane constantly biased to provide a smaller and smaller internal containment area as the contents of the container are decreased or used. Examples of such arrangements may be found in the following U.S. patents:
U.S. Pat. No. 4,865,224 to D. A. Streck PA1 U.S. Pat. No. 5,012,956 to W. R. Stoody PA1 U.S. Pat. No. 4,420,101 to R. K. O'Neill PA1 U.S. Pat. No. 5,037,005 to P. Appleby et al. PA1 U.S. Pat. No. 5,141,136 to J. H. Tignor PA1 U.S. Pat. No. 5,186,346 to J. H. Calvert
The second principle manner for decreasing the time necessary for viscous liquid material to reach the dispensing orifice of a bottle or other dispenser is simply to have the dispensing orifice located at or near the bottom of the container where gravity maintains the liquid to be dispensed always adjacent to such dispensing orifice. The principle difficulty with this arrangement is that the valve at the orifice is likely to leak and either a separate back-up valve must be used or a more complicated combined vent and dispensing orifice valve used at the bottom. Examples of this type of arrangement are shown in the following U.S. Patents:
The Tignor U.S. Pat. No. 5,141,136 also combines a flexible side wall with an opening at the bottom and the Calvert U.S. Pat. No. 5,186,346 incorporates an opening which is at the bottom of the container only part of the time.
A further type of quick dispenser uses a so-called dip-tube in the bottle or container the entrance to which dip-tube is always located near the bottom of the container so that the opening to the tube is always in or immediately adjacent to the liquid material. An example of this is disclosed in U.S. Pat. No. 5,127,553 to J. Weinstein. Dip tubes must be combined with some form of pressure or pumping arrangement and are usually not too effective with viscous liquids because the dip tube almost inherently has a rather restricted inner diameter which may offer a significant impediment to easy flow of a viscous liquid and if any sort of actual pump is used to urge the liquid through the dip tube, such pump is even more likely to have its operations impeded by the viscous liquid, particularly as such liquid ages.
The Appleby et al. U.S. Pat. No. 5,037,005, listed above with respect to bottom mounted openings in particular, discloses a bottle having a tapered shape with an opening or valve located adjacent the bottom near one corner of the smaller end. Appleby et al. discloses the advantage of maintaining the contents of a container always at the bottom of a dispenser against a dispensing valve in a squeezable container with the internal walls generally inclined toward the area of the container having the valve in it. However, while the Appleby et al. arrangement has certain advantages, it has not become popular, in part because of its relatively complicated structure and the likelihood of leakage due to the type of valve used which combines the function of an outlet for viscous liquid and an inlet for air to take the place of such liquid.
There has been a need, therefore, for a dispensing container for relatively viscous liquids that will readily and easily dispense such liquids upon demand, is leak proof between uses and is easy and convenient to use and has the entire interior of the container available for containment of liquid.